[gemini] fixes for benchmarking (#5847)

* [gemini] fix missing return

* [gemini] fix missing arg pass

* [gemini] use gather tensor instead of list

* [test] enable flash attention for benchmark by default

* [test] enable flash attention for benchmark by default

---------

Co-authored-by: genghaozhe <939857490@qq.com>

colossalai/booster/plugin/gemini_plugin.py

@@ -369,9 +369,9 @@ class GeminiPlugin(DPPluginBase):
         assert precision in SUPPORTED_PRECISION, f"precision {precision} is not supported"
         if get_accelerator().name == "npu":
             assert placement_policy == "static", "NPU only supports static placement policy"
-        if placement_policy == "auto" and enable_async_reduce:
+        if enable_async_reduce and not pin_memory:
             logging.warning(
-                f"enable_async_reduce requires pin_memory to achieve best performance, which is not implicitly set."
+                f"enable_async_reduce sets pin_memory=True to achieve best performance, which is not implicitly set."
             )
             pin_memory = True
         self.gemini_config = dict(

colossalai/zero/gemini/chunk/chunk.py

@@ -403,9 +403,9 @@ class Chunk:
                 self.shard_size, dtype=self.dtype, device=get_accelerator().get_current_device()
             )
 
-            input_list = list(torch.chunk(self.cuda_global_chunk, chunks=self.pg_size, dim=0))
-            self.grad_reduce_work = dist.reduce_scatter(
-                self.cuda_shard, input_list, group=self.torch_pg, async_op=async_op
+            assert self.cuda_global_chunk.is_contiguous()
+            self.grad_reduce_work = dist.reduce_scatter_tensor(
+                self.cuda_shard, self.cuda_global_chunk, group=self.torch_pg, async_op=async_op
             )
 
             if self.extra_dp_group is not None:
@@ -520,8 +520,10 @@ class Chunk:
             assert self.cuda_shard is not None
 
             alloc_storage(self.cuda_global_chunk)
-            gather_list = list(torch.chunk(input=self.cuda_global_chunk, chunks=self.pg_size, dim=0))
-            work = dist.all_gather(gather_list, self.cuda_shard, self.torch_pg, async_op=async_op)
+            assert self.cuda_global_chunk.is_contiguous()
+            work = dist.all_gather_into_tensor(
+                self.cuda_global_chunk, self.cuda_shard, self.torch_pg, async_op=async_op
+            )
 
             self.cuda_shard = None
             self.is_gathered = True

colossalai/zero/gemini/chunk/manager.py

@@ -133,12 +133,12 @@ class ChunkManager:
             self.__sub_accessed_chunk(chunk)
             self.__add_memory_usage(chunk.memory_usage)
 
-    def move_chunk(self, chunk: Chunk, device: torch.device, force_copy: bool = False) -> None:
+    def move_chunk(self, chunk: Chunk, device: torch.device, force_copy: bool = False, async_move=False) -> None:
         """Move the shard of the chunk to the target device."""
         if not chunk.can_move or chunk.device_type == device.type:
             return
         self.__sub_memory_usage(chunk.memory_usage)
-        chunk.shard_move(device, force_copy)
+        chunk.shard_move(device, force_copy, non_blocking=async_move)
         self.__add_memory_usage(chunk.memory_usage)
 
     def trans_tensor_state(self, tensor: torch.Tensor, state: TensorState) -> None:

colossalai/zero/gemini/gemini_ddp.py

@@ -387,6 +387,7 @@ class GeminiDDP(ModelWrapper):
         p: nn.Parameter,
         async_reduce_stream: Optional[torch.cuda.Stream] = None,
     ):
+        async_reduce_scatter = async_reduce_stream is not None
         setattr(p, "_gemini_reduced", True)
         empty_grad = torch.empty_like(grad)
         free_storage(empty_grad)
@@ -426,7 +427,7 @@ class GeminiDDP(ModelWrapper):
                 async_reduce_stream.wait_stream(torch.cuda.current_stream())
 
             with torch.cuda.stream(async_reduce_stream):
-                reduced = chunk_manager.reduce_chunk(grad_chunk, async_op=(async_reduce_stream is not None))
+                reduced = chunk_manager.reduce_chunk(grad_chunk, async_op=async_reduce_scatter)
                 if reduced:
                     grad_chunk.wait_async_reduce()
                     if not chunk_manager.reuse_fp16_chunk:
@@ -447,9 +448,13 @@ class GeminiDDP(ModelWrapper):
                     # record l2 norm for gradient clipping. flag is bound to fp16 chunk
                     if chunk.l2_norm_flag:
                         grad_chunk.set_l2_norm()
-                    chunk_manager.move_chunk(grad_chunk, grads_device[p], force_copy=True)
+                    chunk_manager.move_chunk(
+                        grad_chunk, grads_device[p], force_copy=True, async_move=async_reduce_scatter
+                    )
                     if not (master_weights) or (enable_gradient_accumulation):
-                        chunk_manager.move_chunk(chunk, grads_device[p], force_copy=True)
+                        chunk_manager.move_chunk(
+                            chunk, grads_device[p], force_copy=True, async_move=async_reduce_scatter
+                        )
         return empty_grad
 
     def zero_grad(self, set_to_none: bool = False) -> None:

examples/language/llama/benchmark.py

@@ -253,8 +253,13 @@ def main():
         init_kwargs["empty_init"] = False
 
     with init_ctx:
-        model = AutoModelForCausalLM.from_config(config, trust_remote_code=True, **init_kwargs)
-
+        model = AutoModelForCausalLM.from_config(
+            config,
+            trust_remote_code=True,
+            **init_kwargs,
+            attn_implementation="flash_attention_2",
+            torch_dtype=torch.bfloat16,
+        )
     if args.grad_checkpoint:
         model.gradient_checkpointing_enable()
         if config.model_type == "chatglm":
@@ -286,7 +291,7 @@ def main():
 
     with get_profile_context(
         args.profile,
-        1,
+        args.ignore_steps,
         len(dataloader) - 1,
         save_dir=f"profile/{time.strftime('%H:%M', time.localtime())}-{args.plugin}-llama-{args.config}",
     ) as prof: